Jökull - 01.10.1998, Page 18

Brúarjökull is a large surge-type outlet glacier
with a surge period of 70-100 years. It is known to ad-
vance 8-10 km during surges (Thorarinsson, 1969),
which are the most dramatic surges of glaciers in Ice-
land. It has been monitored sporadically since 1963.
Kverkjökull is an outlet glacier from the summit
caldera of Kverkfjöll which has been monitored since
1971 by the National Energy Authority.
Tungnaárjökull is a surge-type outlet glacier
which surged in 1945-46 and in 1994-95. It is 40 km
along the centre line and drains 169 km2 (235 km2
within ice divides) of the ice cap (Björnsson, 1988). It
has been monitored since 1955 by members of the
Iceland Glaciological Society. Variations of Tung-
naárjökull, including the surge of 1945-46, are de-
scribed in Guðmundsson and Bjömsson (1992).
Síðujökull is a surge-type outlet glacier with a
surge period of about 30 years. It surged in 1934,
1963-64 and 1994. It has been monitored at two adja-
cent locations since 1964 by members of the Iceland
Glaciological Society.
HOFSJÖKULL
Hofsjökull is circular ice cap in central Iceland
with many outlet glaciers (Fig. 5). The area was esti-
mated 923 km2 by Bjömsson (1988) based on several
different sources. The ice cap covers a central volcano
with a big caldera. Post glacial volcanic activity with-
1: Blágnípujökull, Hofsjökli
2: Nauthagajökull, Hofsjökli
3: Múlajökull, suður, Hofsjökli
4: Sátujökull, Hofsjökli
5: Hagafellsjökull vestari, staður 2, Langjökli
6: Hagafellsjökull eystri, Langjökli
7: Jökulkrókur, staður 1, Langjökli
8: Jökulkrókur, staður 2, Langjökli
9: Norðurkinn, austur, Hrútfelli (Regnbúðaj.)
10: Norðurkinn, mið, Hrútfelli (Regnbúðaj.)
11: Norðurkinn, vestur, Hrútfelli (Regnbúöaj.)
12: Norðvesturjökull, Hrútfelli (Regnbúðaj.)
13: Loðmundarjökull, Kerlingarfjöllum
Fig. 12. Glacier variations of Hofsjökull, Langjökull, Hrútfellsjökull and Loðmundarjökull.
-Jöklabreytingar, Hofsjökull, Langjökull, Hrútfellsjökull and Loðmundaijökull.
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JOKULL, No. 45, 1998